Steps to Craft a Letter of Acceptance of a Job Offer: 1. Express Gratitude 2.A sample letter offering a job contingent upon the results of a background check or other criteria. An offer letter is a document that holds the terms of employment for a new hire. It includes the salary, benefits, and other important information. The answer to your question, regarding whether you can back out of the Offer Letter, is likely "Yes. Customarily, in the US, it is three days. This recruitment may be used to fill multiple positions in other divisions or departments. Search and apply for federal jobs. Learn about unique hiring paths for veterans, students and graduates, individuals with a disability, and more.